This patent application is a continuation-in-part application to Ser. No. 07/022,027 entitled "Flowmeter with pivotably floating fluid dynamic target" filed on Mar. 5, 1987, now U.S. Pat. No. 4,777,830.
One of the most common methods employed in the measurement of the fluid flow is to measure the dynamic pressure of the fluid flow that is equal to one half of the fluid density times the square of the fluid velocity, wherefrom the rate of volume flow and/or mass flow is determined after substituting the known or measured value of the fluid density thereinto. With few exceptions, the dynamic pressure of the fluid flow is measured by a Pitot tube of one or another type of design. As the dynamic pressure is proportional to the square of the fluid velocity, the magnitude thereof becomes very small when the fluid velocity is very low. A device such as the Pitot tube that directly measures the dynamic pressure without an amplification means, is not capable of measuring the low velocity of the fluid flow. One way to amplify the dynamic pressure in the flow measurement thereby is to measure the force or displacement of a fluid dynamic target with a large fluid dynamic surface created by the dynamic pressure acting thereon.